US5696407A - Process for the production of spherulitic particles - Google Patents
Process for the production of spherulitic particles Download PDFInfo
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- US5696407A US5696407A US08/731,174 US73117496A US5696407A US 5696407 A US5696407 A US 5696407A US 73117496 A US73117496 A US 73117496A US 5696407 A US5696407 A US 5696407A
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- nitroguanidine
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C277/00—Preparation of guanidine or its derivatives, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups
- C07C277/08—Preparation of guanidine or its derivatives, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups of substituted guanidines
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
- C06B21/0091—Elimination of undesirable or temporary components of an intermediate or finished product, e.g. making porous or low density products, purifying, stabilising, drying; Deactivating; Reclaiming
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B25/00—Compositions containing a nitrated organic compound
- C06B25/34—Compositions containing a nitrated organic compound the compound being a nitrated acyclic, alicyclic or heterocyclic amine
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C279/00—Derivatives of guanidine, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups
- C07C279/30—Derivatives of guanidine, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups having nitrogen atoms of guanidine groups bound to nitro or nitroso groups
- C07C279/32—N-nitroguanidines
- C07C279/34—N-nitroguanidine
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S149/00—Explosive and thermic compositions or charges
- Y10S149/11—Particle size of a component
- Y10S149/111—Nitrated organic compound
Definitions
- the invention relates to a process for the production of spherulitic nitroguanidine having a high bulk and tap density, in that nitroguanidine is dissolved in dipolar aprotic solvents, e.g. DMF, DMSO, NMP, etc., by heating to above the saturation temperature t s and the supersaturated solution is cooled with a controlled temperature gradient (°C./min), crystallization being assisted by the addition of particulate, spherulitic material.
- dipolar aprotic solvents e.g. DMF, DMSO, NMP, etc.
- Nitroguanidine is used as a propellant and explosive, whose detonation velocity is higher than that of TNT and which, due to its insusceptibility to shock and higher energy density, offers certain advantages compared with conventional explosive materials.
- nitroguanidine suffers from the disadvantage that during production it is in the form of long, thin needles, which leads to numerous problems, inter alia a very low bulk density.
- known processes are directed at obtaining a compact crystal shape.
- the starting product is once again a hot, saturated solution, which is circulated with a clearly defined stirring efficiency and in which during the cooling phase and prior to the start of self-nucleation, intrinsic seed particles with a diameter of >50 ⁇ m are added.
- the ideal spherical nitroguanidine yield is low.
- the problem of the invention is to so further develop the first-mentioned process that nitroguanidine is obtained as a spherical crystallizate with a high yield and in particular in which the mother liquor can be returned to the crystallization process.
- this problem is solved in that, during heating to above the saturation temperature t s , regularly spherical control particles with a diameter of 5 to 500 ⁇ m are added to the solution in a quantity of 0.05 to 5.00 mass %, said particle size being chosen in such a way that, as a function of the solution behaviour of the nitroguanidine used and its concentration, on dropping below the saturation temperature spherical control particles are still present in the supersaturated solution in the indicated quantity.
- FIG. 1 shows in a diagrammatical view the concentration course of Nitroguanidine during cooling with two different cooling rates
- FIGS. 2A and 2B are shows macrophotographs of a crystallizate produced according to the art
- FIG. 3 shows macrophotographs of a crystallizate obtained by the method according to the invention.
- Seeding with in particular intrinsic seed particles known in crystallization technology is the intentional introduction of nuclei into the supersaturated or supercooled mother phase. This seeding always takes place during the cooling process in solution-cooling-crystallization, including in the first-mentioned process (DE 3,527,200). Unlike in the case of conventional seeding, in the process according to the invention regularly spherical control particles are added to the warming phase or to the start of the cooling phase and prior to reaching the saturation temperature.
- control particles control and check during the cooling the states in the mother liquor after exceeding the saturation limit and eliminate disturbing influences, e.g. as a result of existing or forming unfavourable structures in the mother liquor or through impurities.
- the control action of the particles is ended as soon as the formation of new and clearly defined, regular nuclei initiated by conditioning starts and they then spontaneously continue to grow. It is also possible to avoid the formation of so-called nuclear clouds occurring at low temperature, i.e. a very large number of nuclei, which very rapidly lead to agglomerates.
- the control particles leads to a kinetically defined crystallization, so that supersaturation is controlled in a defined manner. However, with a kinetically undefined crystallization the quality of the crystallizate is subject to the random kinetic interactions.
- the defined addition of control particles under defined conditions to the hot, unsaturated solution is referred to as the conditioning of the residual solution.
- the prerequisite for this function of the control particles is its regular spherical shape and its size limited to a diameter of 5 to 500 ⁇ m, as well as its quantity of 0.05 to 5.00 mass %. If the control particles are added during the warming phase, then the particle size will tend to be larger, so as to take account of the dissolving process acting on the control particles and so as to have in the cooling phase control particles with an adequately large size. However, if the control particles are added at above the saturation temperature during the commencing cooling phase, generally smaller particles will be chosen, so that the control particles are not significantly dissolved.
- control particles are added in a temperature range between t s and t s +50 K, i.e. towards the end of the warming phase or the start of the cooling phase.
- the precipitating crystallizate is absolutely spherical and has a dense structure, so that high bulk density and tap density nitroguanidine is obtained.
- control particles spherical nitroguanidine, so as to avoid different types of chemical or mechanical influences on the crystallizate.
- the process according to the invention offers the possibility of concentrating with nitroguanidine the mother liquor left behind after the crystallization process and, accompanied by further addition of control particles, to again heat it to above the saturation temperature and subject it to a further crystallization process. Practical tests have revealed that the mother liquor can be recirculated up to 10 times without the crystallizate quality suffering or the yield being reduced. Through the addition of fresh solution and mixing of recycled mother liquor, the number of crystallization cycles can be increased.
- FIG. 1 shows the nitroguanidine concentration course during cooling for two different cooling speeds.
- the concentration curve passes horizontally through the saturation curve.
- the concentration drops very rapidly in a medium temperature range.
- Nucleation starts spontaneously.
- the concentration drop is decisively influenced by the course of the saturation curve.
- For higher cooling speeds of 8.5° C./min. there is a much greater supersaturation in the solution and nucleation starts later.
- Table 1 summarizes the essential data for producing the control particles, which are characterized by a spherical shape and a smooth surface.
- the test according to Table 2 shows in the upper part for the nitroguanidine/DMF system and with a fresh batch a good spherulitic particle shape, as well as a good tap density and yield.
- the lower part gives the test data and results for batches concomitantly using the mother liquor from the test in the upper part of the Table. This gives a very irregular particle shape, so that the tap density and yield were not determined.
- Table 4 gives the same test data and results for the nitroguanidine/NMP system.
- the conditioning with the control particles shows that, despite the reuse of the mother liquor, the crystallizate particle shape is not negatively influenced and an only insignificantly lower tap density is made good by a much higher yield.
- FIGS. 2A and 2B are shows macrophotographs of a crystallizate obtained from a solution batch accompanied by the concomitant use of mother liquor, but without adding control particles (e.g. Table 2, lower part), whereas FIGS. 3A and 3B are shows a crystallizate obtained in accordance with the invention, i.e. with conditioning by spherical control particles.
- control particles e.g. Table 2, lower part
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Abstract
In the production of spherulitic nitroguanidine having a high bulk and tapensity nitroguanidine is dissolved in dipolar, aprotic solvents, e.g. DMF, DMSO, NMP, etc., by heating to above the saturation temperature ts and the supersaturated solution is cooled with a controlled temperature gradient (°C./min), crystallization being assisted by the addition of particulate, spherulitic material. In order to obtain spherical nitroguanidine with high yield in a continuous process and with mother liquor reuse, during the heating to above the saturation temperature ts, spherical control particles with a diameter of 5 to 500 μm are regularly added to the solution in a quantity of 0.05 to 5.00 mass %. The particle size is chosen in such a way that, as a function of the solution behaviour of the nitroguanidine used and its concentration, on dropping below the saturation temperature spherical control particles are still present in the indicated quantity in the supersaturated solution.
Description
This application is a Continuation of application Ser. No. 08/326,839, filed Oct. 21, 1994, and now abandoned.
The invention relates to a process for the production of spherulitic nitroguanidine having a high bulk and tap density, in that nitroguanidine is dissolved in dipolar aprotic solvents, e.g. DMF, DMSO, NMP, etc., by heating to above the saturation temperature ts and the supersaturated solution is cooled with a controlled temperature gradient (°C./min), crystallization being assisted by the addition of particulate, spherulitic material.
Nitroguanidine is used as a propellant and explosive, whose detonation velocity is higher than that of TNT and which, due to its insusceptibility to shock and higher energy density, offers certain advantages compared with conventional explosive materials. However, nitroguanidine suffers from the disadvantage that during production it is in the form of long, thin needles, which leads to numerous problems, inter alia a very low bulk density. Thus, known processes are directed at obtaining a compact crystal shape.
Thus, it is known (EP 2 740), to dissolve nitroguanidine in aliphatic alcohols, their monoalkyl or dialkyl ethers, dimethyl formamide (DMF) or dimethyl sulphoxide (DMSO) by heating to saturation temperature and, accompanied by stirring, to cool the solution at a temperature gradient of more than 3 K/min., crystallization starting at temperatures below 50° C. In addition, a recrystallization process is described, in which the hot nitroguanidine solution is poured into a second, cold solvent, in which nitroguanidine is not or is only soluble with difficulty. Although this process leads to more compact nitroguanidine crystals, the yield of ideal spherical nitroguanidine is small.
In the first-mentioned process (DE 3,527,200), the starting product is once again a hot, saturated solution, which is circulated with a clearly defined stirring efficiency and in which during the cooling phase and prior to the start of self-nucleation, intrinsic seed particles with a diameter of >50 μm are added. However, also in this process the ideal spherical nitroguanidine yield is low.
Both the aforementioned processes can only be carried out on a technical scale in batch operation and exclusively with fresh batches, which are therefore prepared from fresh nitroguanidine and solvents. However, it is not possible to reuse the mother liquor and the latter must be disposed of after each crystallization process. This leads to a high raw material use, with low economics and environmental incompatibility.
The problem of the invention is to so further develop the first-mentioned process that nitroguanidine is obtained as a spherical crystallizate with a high yield and in particular in which the mother liquor can be returned to the crystallization process.
According to the invention this problem is solved in that, during heating to above the saturation temperature ts, regularly spherical control particles with a diameter of 5 to 500 μm are added to the solution in a quantity of 0.05 to 5.00 mass %, said particle size being chosen in such a way that, as a function of the solution behaviour of the nitroguanidine used and its concentration, on dropping below the saturation temperature spherical control particles are still present in the supersaturated solution in the indicated quantity.
FIG. 1 shows in a diagrammatical view the concentration course of Nitroguanidine during cooling with two different cooling rates;
FIGS. 2A and 2B are shows macrophotographs of a crystallizate produced according to the art;
FIG. 3 shows macrophotographs of a crystallizate obtained by the method according to the invention.
Seeding with in particular intrinsic seed particles known in crystallization technology is the intentional introduction of nuclei into the supersaturated or supercooled mother phase. This seeding always takes place during the cooling process in solution-cooling-crystallization, including in the first-mentioned process (DE 3,527,200). Unlike in the case of conventional seeding, in the process according to the invention regularly spherical control particles are added to the warming phase or to the start of the cooling phase and prior to reaching the saturation temperature.
These particles control and check during the cooling the states in the mother liquor after exceeding the saturation limit and eliminate disturbing influences, e.g. as a result of existing or forming unfavourable structures in the mother liquor or through impurities. The control action of the particles is ended as soon as the formation of new and clearly defined, regular nuclei initiated by conditioning starts and they then spontaneously continue to grow. It is also possible to avoid the formation of so-called nuclear clouds occurring at low temperature, i.e. a very large number of nuclei, which very rapidly lead to agglomerates. The control particles leads to a kinetically defined crystallization, so that supersaturation is controlled in a defined manner. However, with a kinetically undefined crystallization the quality of the crystallizate is subject to the random kinetic interactions. The defined addition of control particles under defined conditions to the hot, unsaturated solution is referred to as the conditioning of the residual solution.
The prerequisite for this function of the control particles is its regular spherical shape and its size limited to a diameter of 5 to 500 μm, as well as its quantity of 0.05 to 5.00 mass %. If the control particles are added during the warming phase, then the particle size will tend to be larger, so as to take account of the dissolving process acting on the control particles and so as to have in the cooling phase control particles with an adequately large size. However, if the control particles are added at above the saturation temperature during the commencing cooling phase, generally smaller particles will be chosen, so that the control particles are not significantly dissolved. For the initial dissolving of the control particles and therefore for the choice of the particle size vital attention is not only paid to the residence time until dropping below the saturation temperature, but also the solution behaviour of the nitroguanidine used and its concentration. The influence of these parameters on the choice of the particle size can easily be determined by testing.
Preferably the control particles are added in a temperature range between ts and ts +50 K, i.e. towards the end of the warming phase or the start of the cooling phase.
In such a procedure it has proved advantageous to add control particles with a diameter of 60 to 90 μm and in a quantity of 0.4 mass %. The precipitating crystallizate is absolutely spherical and has a dense structure, so that high bulk density and tap density nitroguanidine is obtained.
It is also advantageous to use as the control particles spherical nitroguanidine, so as to avoid different types of chemical or mechanical influences on the crystallizate.
It has also proved advantageous to cool the supersaturated solution with a temperature gradient of >0.5 K/min., the concentration drop below the saturation temperature at low cooling rates approximately following the saturation curve, whereas a greater supersaturation can be set for high cooling speeds.
The process according to the invention offers the possibility of concentrating with nitroguanidine the mother liquor left behind after the crystallization process and, accompanied by further addition of control particles, to again heat it to above the saturation temperature and subject it to a further crystallization process. Practical tests have revealed that the mother liquor can be recirculated up to 10 times without the crystallizate quality suffering or the yield being reduced. Through the addition of fresh solution and mixing of recycled mother liquor, the number of crystallization cycles can be increased.
To facilitate understanding, FIG. 1 shows the nitroguanidine concentration course during cooling for two different cooling speeds. The concentration curve passes horizontally through the saturation curve. With a small cooling speed of 1.2° C./min., the concentration drops very rapidly in a medium temperature range. Nucleation starts spontaneously. The concentration drop is decisively influenced by the course of the saturation curve. For higher cooling speeds of 8.5° C./min., there is a much greater supersaturation in the solution and nucleation starts later.
A number of tests are reproduced below.
TABLE 1
______________________________________
Material system
* Nitroguanidine/NMP (N-methyl-pyrrolidone)
Nitroguanidine concentration
ξNigu:
25.9 mass %
Water concentration (addition)
ξw : 4.5 mass %
Cooling speed ζ':
3.8 °C./min
Crystal-nucleation temperature
ζK,B:
50° C.
Crystallization final temperature
ζK,E:
20° C.
Residence time at final temperature
ζK,E:
10 min
Particle shape : spherical,
smooth
surface
______________________________________
TABLE 2
______________________________________
Material system
* Nitroguanidine/DMF (dimethyl formamide)
Fresh batch
Concentration nitroguanidine
ξNigu:
24.5 mass %
Cooling rate ζ':
4.6° C./min
Crystal-nucleation temperature
ζK,B:
49° C.
Crystallization final temperature
ζK,E:
20° C.
Nitroguanidine concentration at
ζK,E:
16.1 mass %
Supersaturation at ζK,E:
1.32
Tap density σK : 0.95 g/cm.sup.3
Yield φ : 42.9%
Particle shape Φ : spherical,
smooth
surface
______________________________________
______________________________________
Batches with mother liquor reuse (without conditioning)
Nitroguanidine concentration
ξNigu: 23.1 mass %
Cooling rate ζ': 4.6° C./min
Crystal-nucleation temperature
ζK,B: 49° C.
Crystallization final temperature
ζK,E: 20° C.
Nitroguanidine concentration at
ζK,E: 14.2 mass %
Supersaturation at
ζK,E: 1.13
Particle shape Φ
: irregular
Tap density σK
: not determined
due to poor particle
Yield : shape
______________________________________
TABLE 3
______________________________________
Material system
* Nitroguanidine/DMF
Fresh batch
Nitroguanidine concentration
ξNigu:
24.5 mass %
Cooling speed ζ': 4.6° C./min
Crystal-nucleation temperature
ζK,B:
49° C.
Crystallization final temperature
ζK,E:
20° C.
Nitroguanidine concentration at
ζK,E:
16.1 mass %
Supersaturation at
ζK,E:
1.32
Particle shape Φ
: spherical, smooth
surface
Tap density σK
: 0.95 g/cm.sup.3
Yield φ : 42.5%
______________________________________
______________________________________
Batches with mother liquor reuse (with conditioning).
Nitroguanidine concentration
ξNigu:
23.1 mass %
Cooling speed ζ': 4.6° C./min
Addition of control particles:
Nitroguanidine, recrystallized,
: 0.4 mass %
concentration of control particles
χS,K (related to the dissolved
material quantity)
Particle size for control
: (63-90) μm
particles χS,K
Particle shape Φ
: spherical, smooth
at temperature ζS,K
: 95° C.
Crystal-nucleation temperature
: 67° C.
(turbidity point) ζK,B
Crystallization final temperature
ζK,E:
20 ° C.
Nitroguanidine concentration at
ζK,E:
15 mass %
Supersaturation at ζK,E
: 1.19
Particle shape Φ
: spherical, smooth
surface
Tap density σK
: 0.94 g/cm.sup.3
Yield φ : 40.5%
* Temperature at saturation
: 93° C.
concentration t.sub.s
______________________________________
TABLE 4
______________________________________
Material system
* Nitroguanidine/NMP
Fresh batch
Nitroguanidine concentration
ξNigu:
29.8 mass %
Cooling speed ζ': 3.7° C./min
Crystal-nucleation temperature
ζK,B:
54° C.
Crystallization final temperature
ζK,E:
20° C.
Nitroguanidine concentration at
ζK,E:
25.3 mass %
Supersaturation at
ζK,E:
1.45
Residence time at ζK,E
: 30 min
Particle shape σ
: spherical, smooth
surface
Tap density ΦK
: 1.10 g/cm.sup.3
Yield φ : 10.5%
______________________________________
______________________________________
Nitroguanidine concentration
ξNigu:
25.9 mass %
Cooling speed ζ':
3.4° C./min
Addition of control particles:
Nitroguanidine, recrystallized,
: 0.4 mass %
concentration ξS,K (based on
dissolved material quantity)
Particle size χS,K
: (63-90) μm
Particle shape σ
: spherical, smooth
surface
at temperature ζS,K
: 97° C.
Crystal-nucleation temperature
: 75° C.
(turbidity point) ζK,B
Crystallization final temperature ζK,E
: 20° C.
Nitroguanidine concentration at ζK,E
: 21.8 mass %
Supersaturation at ζK,E
: 1.25
Particle shape Φ : spherical, smooth
Tap density σK : 0.99 g/cm.sup.3
Yield φ : 23.7%
* Temperature at saturation concentration t.sub.s
: 95° C.
______________________________________
Table 1 summarizes the essential data for producing the control particles, which are characterized by a spherical shape and a smooth surface.
The test according to Table 2 shows in the upper part for the nitroguanidine/DMF system and with a fresh batch a good spherulitic particle shape, as well as a good tap density and yield. The lower part gives the test data and results for batches concomitantly using the mother liquor from the test in the upper part of the Table. This gives a very irregular particle shape, so that the tap density and yield were not determined.
In upper part of Table 3 are given the test data and results for a fresh batch of the nitroguanidine/DMF system. Once again with a fresh batch there is a high quality particle shape, as well as a satisfactory tap density and yield. The lower part of the Table gives the results when reusing the mother liquor and adding control particles. The Table shows that, despite the reuse of the mother liquor, neither the particle shape, nor the tap density and yield suffered. For the same cooling speed there is a lower supersaturation than with the fresh batch. The statistical evaluation of the test series has generally shown that the less low the supersaturation the closer the spherical particle shape comes to the ideal shape, or conversely the lower the supersaturation the worse the particle shape and therefore the tap density.
Table 4 gives the same test data and results for the nitroguanidine/NMP system. Here again the conditioning with the control particles shows that, despite the reuse of the mother liquor, the crystallizate particle shape is not negatively influenced and an only insignificantly lower tap density is made good by a much higher yield.
FIGS. 2A and 2B are shows macrophotographs of a crystallizate obtained from a solution batch accompanied by the concomitant use of mother liquor, but without adding control particles (e.g. Table 2, lower part), whereas FIGS. 3A and 3B are shows a crystallizate obtained in accordance with the invention, i.e. with conditioning by spherical control particles.
Claims (10)
1. A process for the production of spherulitic nitroguanidine having a high bulk and tap density, comprising:
forming a solution by dissolving nitroguanidine in a dipolar aprotic solvent by heating to above the saturation temperature;
adding regularly spherical control particles to the solution; and
cooling the solution having the regularly spherical control particles therein to below the saturation temperature at a controlled temperature gradient;
wherein the regularly spherical control particles are added in an amount and with a particle diameter such that, on dropping below the saturation temperature during the cooling, the regularly spherical control particles have a diameter of 5 to 500 μm and are present in an amount of 0.05 to 5.00 mass %, wherein crystallization of the nitroguanidine is assisted by the regularly spherical control particles to yield a crystallizate of nitroguanidine having a spherical shape and high bulk and tap density.
2. Process according to claim 1, characterized in that the regularly spherical control particles are added in a temperature range between the saturation temperature and the saturation temperature +50 K.
3. Process according to claim 1, characterized in that the regularly spherical control particles are added with a diameter of 60 to 90 μm.
4. Process according to claim 3, characterized in that the regularly spherical control particles are added in a quantity of 0.4 mass %.
5. Process according to claim 1, characterized in that spherical nitroguanidine is used as the regularly spherical control particles.
6. Process according to claim 1, characterized in that the supersaturated solution is cooled with a temperature gradient >0.5° C./min.
7. Process according to claim 1, for the continuous production of spherulitic nitroguanidine, characterized in that the mother liquor left following the crystallization process is concentrated with nitroguanidine and heated to above the saturation temperature again, accompanied by the addition of regularly spherical control particles.
8. Process according to claim 1, wherein said dipolar aprotic solvent is selected from the group consisting of DMF, DMSO and NMP.
9. Process according to claim 1, wherein the regularly spherical particles are added during the cooling prior to reaching the saturation temperature.
10. Process according to claim 1, wherein the regularly spherical particles are added during the heating to above the saturation temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/731,174 US5696407A (en) | 1993-10-22 | 1996-10-07 | Process for the production of spherulitic particles |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4336049.1 | 1993-10-22 | ||
| DE4336049A DE4336049C1 (en) | 1993-10-22 | 1993-10-22 | Process for preparing spherulitic nitroguanidine |
| US32683994A | 1994-10-21 | 1994-10-21 | |
| US08/731,174 US5696407A (en) | 1993-10-22 | 1996-10-07 | Process for the production of spherulitic particles |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US32683994A Continuation | 1993-10-22 | 1994-10-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US5696407A true US5696407A (en) | 1997-12-09 |
Family
ID=6500751
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US08/731,174 Expired - Fee Related US5696407A (en) | 1993-10-22 | 1996-10-07 | Process for the production of spherulitic particles |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US5696407A (en) |
| JP (1) | JPH07252204A (en) |
| DE (1) | DE4336049C1 (en) |
| FR (1) | FR2711652B1 (en) |
| GB (1) | GB2284417B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109186100A (en) * | 2018-10-28 | 2019-01-11 | 山西北化关铝化工有限公司 | Explosive production high-solidification point liquid heating |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19834876A1 (en) * | 1998-08-01 | 2000-02-03 | Aventis Res & Tech Gmbh & Co | Process for the production of spherical particles during crystallization |
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| US2850533A (en) * | 1956-12-13 | 1958-09-02 | American Cyanamid Co | Guanidine nitrate recovery |
| US2949484A (en) * | 1957-08-13 | 1960-08-16 | Pittsburgh Coke & Chemical Co | Preparation of guanidine compounds |
| US3236702A (en) * | 1964-04-08 | 1966-02-22 | Hercules Powder Co Ltd | Manufacture of densified spheroidal fine particle nitrocellulose |
| US3917767A (en) * | 1973-10-16 | 1975-11-04 | Dynamit Nobel Ag | Process for the preparation of multiple-base propellant powder |
| US3928514A (en) * | 1973-04-03 | 1975-12-23 | Dynamit Nobel Ag | Process for the production of gudol powder utilizing reduction of moisture content |
| US4544769A (en) * | 1977-12-17 | 1985-10-01 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. | Process for the preparation of compact nitroguanidine |
| US4967000A (en) * | 1989-09-12 | 1990-10-30 | The United States Of America As Represented By The Department Of Energy | Spherical nitroguanidine process |
| US5389263A (en) * | 1992-05-20 | 1995-02-14 | Phasex Corporation | Gas anti-solvent recrystallization and application for the separation and subsequent processing of RDX and HMX |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3527200A1 (en) * | 1985-07-30 | 1987-03-19 | Horst Dipl Ing Hommel | Process for preparing spherulitic crystals of high bulk density and packing density, in particular of spherically crystalline nitroguanidine |
| DE3605634A1 (en) * | 1986-02-21 | 1987-08-27 | Messerschmitt Boelkow Blohm | Method for treating crystalline explosives for high-explosive charges |
| DE3920999C1 (en) * | 1989-06-27 | 1990-09-06 | Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung Ev, 8000 Muenchen, De | Nitro:guanidine spherical crystals - obtd. by forming nucleating seeds and crystallising by agitated cascade process |
-
1993
- 1993-10-22 DE DE4336049A patent/DE4336049C1/en not_active Expired - Fee Related
-
1994
- 1994-09-28 GB GB9419522A patent/GB2284417B/en not_active Expired - Fee Related
- 1994-10-21 FR FR9412630A patent/FR2711652B1/en not_active Expired - Fee Related
- 1994-10-24 JP JP6282403A patent/JPH07252204A/en active Pending
-
1996
- 1996-10-07 US US08/731,174 patent/US5696407A/en not_active Expired - Fee Related
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2740704A (en) * | 1950-03-09 | 1956-04-03 | Olin Mathieson | Process for producing globular propellent powder grains |
| US2691800A (en) * | 1951-02-10 | 1954-10-19 | Olin Ind Inc | Method of recovering explosives in particular form |
| US2850533A (en) * | 1956-12-13 | 1958-09-02 | American Cyanamid Co | Guanidine nitrate recovery |
| US2949484A (en) * | 1957-08-13 | 1960-08-16 | Pittsburgh Coke & Chemical Co | Preparation of guanidine compounds |
| US3236702A (en) * | 1964-04-08 | 1966-02-22 | Hercules Powder Co Ltd | Manufacture of densified spheroidal fine particle nitrocellulose |
| US3928514A (en) * | 1973-04-03 | 1975-12-23 | Dynamit Nobel Ag | Process for the production of gudol powder utilizing reduction of moisture content |
| US3917767A (en) * | 1973-10-16 | 1975-11-04 | Dynamit Nobel Ag | Process for the preparation of multiple-base propellant powder |
| US4544769A (en) * | 1977-12-17 | 1985-10-01 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. | Process for the preparation of compact nitroguanidine |
| US4967000A (en) * | 1989-09-12 | 1990-10-30 | The United States Of America As Represented By The Department Of Energy | Spherical nitroguanidine process |
| US5389263A (en) * | 1992-05-20 | 1995-02-14 | Phasex Corporation | Gas anti-solvent recrystallization and application for the separation and subsequent processing of RDX and HMX |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109186100A (en) * | 2018-10-28 | 2019-01-11 | 山西北化关铝化工有限公司 | Explosive production high-solidification point liquid heating |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07252204A (en) | 1995-10-03 |
| GB2284417A (en) | 1995-06-07 |
| FR2711652B1 (en) | 1996-07-19 |
| GB9419522D0 (en) | 1994-11-16 |
| FR2711652A1 (en) | 1995-05-05 |
| DE4336049C1 (en) | 1995-03-09 |
| GB2284417B (en) | 1997-06-25 |
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